6 VIRGINIA FORESTS RECOVERY EFFORTS FOR THE Endangered Virginia Round-leaf Birch Discovery Our story about the Virginia round-leaf birch, Betula uber (Ashe) Fernald, begins on June 14, 1914, when U.S. Forest Service forester and botanist William Willard Ashe came upon a round-leaved variant of the common black or sweet birch (Betula lenta L) while conducting surveys along the banks of Dickey Creek in Smyth County, Va., at 2,800 ft. in elevation. He named the variant Betula lenta var. uber, but provided no information on the size dimensions or number of individuals in his 1918 published report. Ashe noted that the leaves were quite distinct, being nearly as wide as long with only three to six pairs of primary veins, and nutlets that were narrowly winged, and its bark typical of black or sweet birch with “characteristic birch oil fragrance and flavor,” that is distinctive due to oil of wintergreen. Renowned botanist Merritt Lydon Fernald, director of Harvard University’s Gray Herbarium, later examined the annotated specimens collected by Ashe and noted that he had made reference to the tree being 20–25 ft. high. Fernald, upon examining the specimens more closely, along with specimens of the typical black or sweet birch, concluded that Ashe’s specimens had little in common with the typical sweet or black birch other than aromatic bark, and thus elevated it to the level of a species, naming it Betula uber (Ashe) Fernald and transferring it from the darkbarked tree-birch section of the genus (series Costatae, which included sweet birch and yellow birch [B. alleghaninesis Britton]) to the shrub section (series Humiles). Fernald noted, in particular, the nearly round leaves with a small number of primary veins as compared to sweet birch with its egg-shaped leaves and 10–20 pairs of primary veins. He further observed that the female fruit clusters (i.e., catkins or aments) were more slender in the former species, and the three-lobed bracts of the catkins (each having three winged nutlets at their base) were less elongate and without a prolonged middle lobe compared to B. lenta. Fernald concluded by stating that “It is very important to learn more about B. uber, whether it is shrubby, the range of variation of foliage, the characters of the staminate (male) ament, and its abundance and range.” Loss and Rediscovery In the years that followed Ashe’s discovery, many attempts were made to relocate B. uber with no success, leading the Smithsonian Institute to conclude in its 1974 report on “Endangered and Threatened Plant Species of the United States” that the species was probably extinct. In 1975, the U.S. Department of Interior reached the same conclusion in its report on “Threatened or Endangered Fauna or Flora” in the Federal Register. Around that same time, Peter Mazzeo, research assistant at the U.S. National Arboretum, reported in his paper published in 1974 that an undated collection of the species by H.B. Ayres—that heretofore had not been known—bore the location as Cressy Creek, the watershed just to the east of Dickey Creek. Doug Ogle, a faculty member at nearby Virginia Highlands Community College in Abingdon, Va., read Mazzeo’s account and set out to locate the species through a systematic search along both Dickey and Cressy Creeks. Ogle came upon the species in a mixed deciduous forest along the banks of Cressy Creek on August 22, 1975 at First-year, round-leaf birch seedling (PHOTO BY TERRY SHARIK, SEPT. 4, 2024) By Terry Sharik, Ph.D.
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